Re: [ovs-dev] can not well distributed when use dp_hash for ovs group
I just submitted v1 of the patch series to the mailing list. Please have a look and comment. BR, Jan > -Original Message- > From: Jan Scheurich > Sent: Tuesday, 20 March, 2018 15:16 > To: 'ychen' <ychen103...@163.com>; d...@openvswitch.org; ja...@ovn.org > Subject: RE: [ovs-dev] can not well distributed when use dp_hash for ovs group > > Hi ychen, > > We have been working on this problem and have a fully working patch that we > will submit to the ML shortly. > We would be glad if you could give it a test and review. > > Thanks, Jan > > > -Original Message- > > From: ovs-dev-boun...@openvswitch.org > > [mailto:ovs-dev-boun...@openvswitch.org] On Behalf Of ychen > > Sent: Tuesday, 20 March, 2018 14:20 > > To: d...@openvswitch.org; ja...@ovn.org > > Subject: [ovs-dev] can not well distributed when use dp_hash for ovs group > > > > hi, > > I tested dp_hash for ovs group, and found that dp_hash can not well > > distributed, some buckets even can not be selected. > > In my testing environment, I have 11 buckets: > > group_id=131841,type=select,selection_method=dp_hash, > > bucket=bucket_id:51162,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.29:80))), > > bucket=bucket_id:42099,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.25:80))), > > bucket=bucket_id:53526,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.27:80))), > > bucket=bucket_id:12221,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.40:80))), > > bucket=bucket_id:2787,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.26:80))), > > bucket=bucket_id:18951,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.24:80))), > > bucket=bucket_id:32559,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.62:80))), > > bucket=bucket_id:35550,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.43:80))), > > bucket=bucket_id:9026,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.57:80))), > > bucket=bucket_id:26811,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.34:80))) > > > > > > But about 3~5 buckets can not be selected always. > > > > > > In the function xlate_dp_hash_select_group(), I found the code: > > uint32_t mask = (1 << log_2_ceil(n_buckets)) - 1; > > uint32_t basis = 0xc2b73583 * (ctx->xin->flow.dp_hash & mask); > > uint32_t score = (hash_int(bucket->bucket_id, basis) & 0x) * > > bucket->weight; > > > > > > for the above formula, if n_buckets is 11, then there are totally 16 > > probabilities for basis. > > so how can we make sure the best score can well distributed in the 11 > > buckets? > > > > ___ > > dev mailing list > > d...@openvswitch.org > > https://mail.openvswitch.org/mailman/listinfo/ovs-dev ___ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
Re: [ovs-dev] can not well distributed when use dp_hash for ovs group
Hi ychen, We have been working on this problem and have a fully working patch that we will submit to the ML shortly. We would be glad if you could give it a test and review. Thanks, Jan > -Original Message- > From: ovs-dev-boun...@openvswitch.org > [mailto:ovs-dev-boun...@openvswitch.org] On Behalf Of ychen > Sent: Tuesday, 20 March, 2018 14:20 > To: d...@openvswitch.org; ja...@ovn.org > Subject: [ovs-dev] can not well distributed when use dp_hash for ovs group > > hi, > I tested dp_hash for ovs group, and found that dp_hash can not well > distributed, some buckets even can not be selected. > In my testing environment, I have 11 buckets: > group_id=131841,type=select,selection_method=dp_hash, > bucket=bucket_id:51162,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.29:80))), > bucket=bucket_id:42099,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.25:80))), > bucket=bucket_id:53526,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.27:80))), > bucket=bucket_id:12221,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.40:80))), > bucket=bucket_id:2787,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.26:80))), > bucket=bucket_id:18951,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.24:80))), > bucket=bucket_id:32559,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.62:80))), > bucket=bucket_id:35550,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.43:80))), > bucket=bucket_id:9026,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.57:80))), > bucket=bucket_id:26811,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]- > >NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.34:80))) > > > But about 3~5 buckets can not be selected always. > > > In the function xlate_dp_hash_select_group(), I found the code: > uint32_t mask = (1 << log_2_ceil(n_buckets)) - 1; > uint32_t basis = 0xc2b73583 * (ctx->xin->flow.dp_hash & mask); > uint32_t score = (hash_int(bucket->bucket_id, basis) & 0x) * > bucket->weight; > > > for the above formula, if n_buckets is 11, then there are totally 16 > probabilities for basis. > so how can we make sure the best score can well distributed in the 11 buckets? > > ___ > dev mailing list > d...@openvswitch.org > https://mail.openvswitch.org/mailman/listinfo/ovs-dev ___ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
[ovs-dev] can not well distributed when use dp_hash for ovs group
hi, I tested dp_hash for ovs group, and found that dp_hash can not well distributed, some buckets even can not be selected. In my testing environment, I have 11 buckets: group_id=131841,type=select,selection_method=dp_hash, bucket=bucket_id:51162,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.29:80))), bucket=bucket_id:42099,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.25:80))), bucket=bucket_id:53526,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.27:80))), bucket=bucket_id:12221,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.40:80))), bucket=bucket_id:2787,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.26:80))), bucket=bucket_id:18951,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.24:80))), bucket=bucket_id:32559,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.62:80))), bucket=bucket_id:35550,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.43:80))), bucket=bucket_id:9026,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.57:80))), bucket=bucket_id:26811,weight:100,actions=ct(commit,table=70,zone=2,exec(move:NXM_OF_ETH_SRC[]->NXM_NX_CT_LABEL[0..47],nat(dst=10.204.8.34:80))) But about 3~5 buckets can not be selected always. In the function xlate_dp_hash_select_group(), I found the code: uint32_t mask = (1 << log_2_ceil(n_buckets)) - 1; uint32_t basis = 0xc2b73583 * (ctx->xin->flow.dp_hash & mask); uint32_t score = (hash_int(bucket->bucket_id, basis) & 0x) * bucket->weight; for the above formula, if n_buckets is 11, then there are totally 16 probabilities for basis. so how can we make sure the best score can well distributed in the 11 buckets? ___ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
